Bearing construction with segmental shoes on flexible resilient supports



Dec. 1 l, 1951 MENTAL SHOE ON ESIL T P ORT May 25, 1947 E. T. P.NEUBAUER 2,577,798

BEARING CONSTRUCTION W SEG LE R SU P i'led FLE V IV /5 5' 4 INVENTORATTORNEY Patented Dec. 11, 1951 BEARING CONSTRUCTION WITH sEG MENTALSHOES N FLEXIBLE RESIL- IENT SUPPORTS Emil T. P. Neubauer, Milwaukee,Wis., assignor to Allis-Chalmers Manufacturing Company, Milwaukee, Wis.,a corporation of Delaware Application May 23, 1947, Serial No. 749,9308-Claims. (Cl. 308-160) This invention relates to rotary shaft bearingsand more particularly to bearings capable of high unit area loading dueto the establishment of a wedge-like oil film under high pressureconditions.

The principles by which bearings of this type are enabled to bear highunit loads are well known and understood, and. such bearings ordinarilyinvolve a number of segments or shoes generally arranged to cooperate informing a generally annular bearing surface, with provision forindividual tilting of the various segments to establish the wedge shapedfilms of lubricant. In some cases, supports for the segments or shoeshave been made resilient, and inmany cases the supports are, in turn,mounted on a self-aligning rigid base ring seated in a spherical bearingseat in the machine frame. Many of the known sup: port arrangements are,however, complicated and expensive.

The present invention concerns a simple arrangement of the segmentalshoes on cantilever shoe supports which extend in a generallycircumferential direction in spaced relation to the base ring orstationary frame. The cantilever supports may be integralwith boththe-shoes and the base ring, and are made sufficiently flexible in thedirection of the load thrust to'permit some slight resilient yielding orcushioning of the-shoe in the direction of the thrust in addition to atilt- Fig. 4 is a partial development of the periphery of the unit shownin Fig. 3;

Fig. 5 is a view similar to Fig. 4 but with an exaggerated distortion toillustrate an operational condition.

As illustrated in the drawing, bearing elements I and 2 according to theinvention are mounted ina thrust housing 3 of conventional construction,held in a machine frame 4' in which a ro-' tary shaft 6 is journaled asat l. Bearing units I and 2 face oppositely and are retained in 1 collaror flange 6', and are made symmetrical to which serves to engage a seat(as 3) of a machine ing of the shoe in the direction of the leadingedge,

a plane midway between their bearing surfaces when in coaxial opposedrelation as shown. Accordingly, only of these elements will be describedin detail, it being understod that the other is reversed as to designedrelative direction of rotation. v

Bearing element I comprises a base ring portion II which may beconsidered as an annular solid having a convex spherical zone surface I2frame in non-rotatable self-aligning relation. Rotation relative to theseat 8 in the arrangement shown, is prevented as by a stud I3 engaging aslot I4 in the seat 8. This base ring portion II may be considered asbounded by an end surface Ifi, an inner peripheral surface I'I, an outerperipheral surface I8, and an imaginary plane perpendicular to the axisof revolution, such as that of line A-A in Fig. 3.

On the base ring portion I I are mounted a plurality (eight shown) ofsegmental bearing shoe drawing which forms a part of this specification,

Fig. 2 is a detail end view of one of the thrust bearing elements ofFig. 1, shown partially 1;"

broken away and in section on the line IIII of Fig. 3;

, Fig. 3 is a side view of the thrust bearing unit of Fig. 2.; r

portions I9 each having a segmental thrust bearing surface 2|. Theseshoe portions or shoes I9 are so mounted, as described below, that theirbearing surfaces 2I normally lie in a common plane or otherwise form asegmented annular bearing surface 22.

a The term annular surface is taken herein as defining any ring-shapedsurface or zone of a 2 surface of revolution, ranging from a truegeoportion II, by means of being formed as cantilever projections on thebase ring, extending in the direction of surface 22, and havingintermediate shoe support portions 23 extending circumferentially of thering portion II, in spaced relationto thebasering portion. It willbeseen that the-portioml} may be madesuflicientlythin (in dimension normalto surface 22, or transverse to its mean longitudinal axis) that it willbe relatively flexible and resilient, compared with the solid ringportion; and it will als o =-be'seen that on any straight linenormal-toa surface Z-I and extending between any point of that surfaceand ring portion II, the ,surface ,-,-is "nowhere backed up or supportedbya solid co1umn -of material in compression. Pressure.onsurfaoell willaccordingly cause yieldingof .the whole shoe IS in the direction of ringportion 'I'l, owing'to flexing of the projection, notably as at shoesuprport portion 23. This flexing of the projection will-,cause yielding andtilting.,of ,the ,shoes 1, as illustrated in exaggeratedfprm, in -Eig.:hand: will promote maintenance of awedge-shaped oil ,fllm between thesurfaces 2| and the engagedsurface of thrust flange 6. The material,,form and dimensions of portion 23.,and shoel-sqcambe so chosen as toobtain suchresilientflexing, under predetermined loading. and operating-cnditi0ns, as to give precisely the desired yield and tilt. Forexample, the width ofthe projectionportion 23 and shoe l9 par.allelto1ageneratingelementof surface '22 will be made substantially greaterthan the thickness of portion 23 to resist .undesired tilting bytorsion, or lateral flexing.

As a whole, the bearingelement can;be ,describedas an annular solidlwithanannular hearing surfaceZZ divided and undercut by a series ofangularly spaced voids 24 of such form as to leave the shoe portions l.9in dividually connected withbase ring portion .l I onlybyrelativelytflexible, resilient, cantilever,,shoe support portions 23extending circumferentially in spaced relation to thebase ringportion.Theseyoids 24 maybe considered as extending. clear through the'ring in adirection generallymarallel,to thegenerating elements of the .bearingsurface. 22, .and .as .extending only from-this surface}; to theimaginary surface of base .ring portion lfl (planefof line AA, Fig. 3),..or,only.a portiomof thedepth of the ring normally .to the bearingsurface Where, as illustrated,.,the bearingsurface 2 2.is a planar,axial thrust bearing surface, the shoe supports 23 and bearing surfaces,2] are spaced from the base ringportionin anaxial direction; and theshoe support portions. 23.,ar e,all arranged to extendin the samedirection of rotation-circumferentially ofthe baseringportion,.in-,a,helical sense, that is, in the direction of relative rotation of the elementwithrespect to :theengaged rotary bearing surface.

Operation of the thrust ringelement vpf vthe invention is self-evidentfrom the illustration, when considered in the light of the'i-well lgnownKingsbury principle (see Kingsbury 1,947,252; 1,102,276 and Fulpius,l,735,3l5). -ielding,-due;to pressure will clearly .be-greaterat-the leading.91 toe ends of the shoes 1-9,,the'tilt-efiect permitting ready entranceof ,oil to form the well known wedge film. Slight generalyieldingofall;poi -nts of the shoes [9 in a common direction znormalzto thesurface, will.give.a highly,desirabl e cushioning effect to the'bearingelementonthe present invention.

The principles of present invention williacilitate the achievement,ofcompactness rand ,sim plicity of design, and low manufacturing costin design procedures known to persons skilled in the art to which thisinvention appertains. And

.venylittlemachinawork will be required to finish the-working surfacesof a precision-cast element.

It'willbeunderstood that the practical embodiment illustrated anddescribed in detail is by .Wayefexample, and that the invention inrcludessuch modifications and equivalents as may readily occur to personsskilled in the art, within '-the'scope of-the appended claims.

I t.,.,i5 claimed and desired to secure by Letters Patent:

1 In a bearing .element, a substantially rigid basering portion,,aplurality of bearing shoe portions having,respective'bearing surfacesadapted to form a segmentedannular bearing surface,.a plurality ofcantilever support portions each connectedatone endto ,said base.ringand at the other end to one of said-shoe portions, each of saidsupport portions extending in a generally circumferential direction fromand in axially bodily spaced relation to said base ring, each of saidbearing surfaces. ,being .circumferentially spaced respectively .fromsaid connection between its ,cantileversupport portionand said basering, .and eachof said support. portionsbeingsufficiently flexible andresilientso that the axial thrust load to be accommodated causesdeflection of said bearingsurfaces.

2. Inabearing element, ,a substantially rigid base ring portion,aplurality of bearing shoe portions having respective bearing surfacesadapted to form asegmentedannular bearingsurface, a plurality ofrelatively,, flexible,resilient,cantilever support portions eachconnected at one end to said base ring andattheothenend to one of saidshoe portions, each of saidlsupport portions extending in a I generallcircumferential. direction fromandin axially bodilysspaced relationtosaid base ring,,each ofsaid bearing surfaces being circumferentiallyspaced. respectively fromsaid connection between itscantilever supportportion and said ,basering, andall of said bearing surfaces normallybeingdn-one planenormal to the .axis Qisaid base ring. when unloadedaxiall ,3. ,In a bearing. element,. a substantially rigid base ringportion, a,plurality of. bearing shoe portions having respective bearingsurfaces adapted to form asegmented annular bearing surface, apluralityof relatively, flexible resilient cantilever supportportionseach connected .at one end to said baseringand. at the other endto one of said shoe portions, each of said support portions extending ina generallycircumferential direction from and'inaxially-bodily'spaced:relation to said basering, each of said-bearing surfaces beingcircumferentially spaced respectively from -said connection'between itscantlleversupport portion and said-base ring, all-of said bearingsurfaces normallybeing krone-plane normal-to the'axis of said base ringwhen unloaded :axially, andeach Y of;said supportzportions beingsufficiently flexible of thrust to a machine frame, a plurality ofcantilever shoe supporting projections each connected at one end to saidbase ring and having a relatively flexible resilient portion extendingcircumferentially of said base ring in axially bodily spaced relationthereto, and a segmented annular bearing surface formed on shoe portionsindividually connected with said ring by said projections, each segmentof said bearing surface respectively occupying a positioncircumferentially spaced from said connection between its cantileversupporting projection and said base ring, and each of said supportportions being sufiiciently flexible and resilient so that the axialload to be accommodated causes deflection of each segment of saidbearing surface.

5. An integral thrust bearing ring comprising, a segmented annularthrust bearing surface, a substantially rigid annular base portion, saidthrust bearing surface being formed on the ends of integral shoeprojections, each said shoe projection having a circumferentiallyextending portion adjacent its junction with said annular base portionin axially bodily spaced relation with said base portion, each segmentof said bearing surface occupying a position circumferentially spacedfrom said junction, and each of said circumferentially extendingportions being sufficiently flexible and resilient so that the axialload to be accommodated causes deflection of each segment of saidbearing surface.

6. A thrust bearing assembly having in combination: shaft means; collarmeans associated with said shaft; annular thrust bearing elementsmounted coaxially of said shaft means in opposed relation for respectivetransfer of thrust from said collar means to a machine frame in eitheraxial direction; each of said bearing elements comprising, asubstantially rigid base ring portion, a plurality of bearing shoeportions having respective bearing surfaces adapted to form a segmentedannular bearing surface for cooperation with said collar means, aplurality of relatively flexible resilient cantilever support portionseach connected at one end to said base ring and at the other end to oneof said shoe portions, each of said support portions extending in agenerally circumferential direction from and in axially bodily spacedrelation to said base ring, each of said bearing surfaces beingcircumferentially spaced respectively from said connection 6 between itscantilever support portion and said base ring in an opposite directionfrom the intended rotational direction of said shaft, and each of saidsupport portions being sufficiently flexible and resilient so that theaxial thrust load to be accommodated causes deflection of said bearingsurfaces.

7. An integral bearing element having a substantially rigid baseportion, a plurality of relatively flexible bearing shoe projections onsaid base ring portion terminating in segmental thrust bearing surfacesspaced normally from said base ring portion, said projections being soformed that no continuous column of the material extends in a directionnormal to said bearing surface between any point of said bearing surfaceand said base ring portion, said bearing shoe projections beingsufficiently flexible so that the axial thrust load to be accommodatedcauses deflection of said segmental bearing surfaces.

8. An integral bearing ring having a plurality of segmental bearingsurfaces forming a segmented annular bearing surface, said ring having asubstantially rigid base portion and being recessed between saidsegmental bearing surfaces and said base portion so that the portions ofsaid ring on which said segmental bearing surfaces are formed arecompletely undercut and are connected with said base portions solely bycircumferentially extending flexible cantilever support portions, saidsupport portions being sufficiently flexible so that the axial thrustload to be accommodated causes deflection of said segmental bearingsurfaces.

EMIL T. P. NEUBAUER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,688,519 Bohn Oct. 23, 19281,991,461 Howarth Feb. 19, 1935 2,424,028 Haeberlein July 15, 1947FOREIGN PATENTS Number Country Date 125,510 Great Britain Apr. 17, 1919405,511 Germany Nov. 20, 1924

